In a large pot, heat some olive oil over medium heat. Add the onion, carrots, celery, and garlic. Cook until the vegetables are softened, about 5-7 minutes.

Add the cumin, coriander, turmeric, and cinnamon to the pot. Stir to coat the vegetables in the spices.

Add the lentils and broth to the pot. Bring to a boil, then reduce heat and simmer for about 25-30 minutes, or until the lentils are tender.

Use an immersion blender to partially blend the soup, leaving some lentils whole for texture. Alternatively, you can transfer a portion of the soup to a blender and blend until smooth, then add it back to the pot.

Season the soup with salt, pepper, and lemon juice to taste.

Serve the Lebanese Lentil Soup hot, garnished with fresh parsley and a drizzle of olive oil. Enjoy!